JPS6347311Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention is an oil path forming device for a hydraulic clutch type transmission that allows gear shifting to be performed by selectively operating multiple hydraulic clutches. A plurality of annular grooves are formed on the peripheral surface of one end of the power shift shaft on which the power shift shaft is mounted, and the plurality of annular grooves are communicated with the plurality of hydraulic clutches through a plurality of oil passages bored in the power shift shaft. The open end is sealed with a fixed seal body fitted onto one end of the power shift shaft to form a plurality of oil distribution chambers for the plurality of hydraulic clutches on the one end of the power shift shaft. The present invention relates to an oil passage forming device for a clutch type transmission.

Since the power shift shaft on which multiple hydraulic clutches are mounted in a hydraulic clutch type transmission is rotated, the oil passage that supplies and discharges hydraulic oil to the multiple hydraulic clutches above it is a rotary joint. Generally, as described above, a plurality of oil distribution chambers are formed between the seal body stationary on one end of the rotating power shift shaft, and the oil passages in the seal body and the power shift shaft are connected to each other. A method is adopted in which the oil passage in the shaft is connected to the oil distribution chamber.

Generally, the above-mentioned seal body is, for example,
As disclosed in Publication No. 37011 and Publication No. 37016 of 1982, a supporting wall (a support wall body (a transmission case wall or a wall surface of a transmission case) that supports one end of the power shift shaft via a bearing It has also been constructed with a one-side blind cylinder mounted on the outer surface of an installed oil passage plate (for forming an oil passage) and fitted onto one end of the power shift shaft. In this structure, the plurality of oil distribution chambers described above are arranged outside of the support wall, so this is particularly useful when the number of oil distribution chambers is increased in response to the large number of hydraulic clutches on the power shift shaft. , the power shift shaft becomes longer.

In this regard, as disclosed in Japanese Patent Application Laid-Open No. 55-110624, when the seal body having the above function is constituted by a supporting wall body that supports one end side of the power shift shaft via a bearing, it is possible to Since the oil distribution chamber is arranged inside the support wall, there is no need for the power shift shaft to protrude outside the support wall for the purpose of forming an oil passage, and the power shift shaft can be shortened. This also simplifies the oil passage forming structure. However, this structure requires an increase in the thickness of the support wall described above, especially when the number of hydraulic clutches on the power shift shaft is large and the number of oil distribution chambers is correspondingly large. Since the support wall has a large area, it is economically disadvantageous.

The purpose of this invention is to provide an oil passage forming device as mentioned at the beginning, which eliminates the above-mentioned problems of conventional devices and also makes it easier to form oil passages. An object of the present invention is to provide a novel oil passage forming device for a device.

This invention will be described in detail below with reference to the illustrated embodiments.

The embodiment shown in FIGS. 1-6 relates to an example in which this invention is implemented in an agricultural tractor as shown in FIG. The tractor has an engine 1 mounted on the front part of the body, and a body part following this engine tower part.
The large diameter portion 2a at the front end includes a clutch housing 2 which houses a main clutch (not shown), and a transmission case 3 which houses a transmission mechanism. The vehicle travels by rotationally driving the left and right rear wheels 4, and by providing a transmission shaft 6 that transmits power from inside the transmission case 3 in the direction of the front wheels 5, and also rotationally driving the left and right front wheels 5 as necessary. It is said that A passenger seat 7 is installed on the transmission case 3, and the vehicle is steered by an operator sitting on the passenger seat 7 turning the left and right front wheels 5 by operating a steering handle 8 in front of the driver. It is supposed to be done. A working machine connected to the rear of the machine is raised and lowered by a hydraulic lift arm 9 and extends rearward from inside the mission case 3.
It receives transmission from the PTO shaft 10 and is driven to rotate.

As shown in FIG. 2, a short case part 3A is attached to the front part of the mission case 3 in the illustrated case, and a supporting wall body 3a constituted by the front wall part of this case part 3A. and a supporting wall part 3b integrally formed with the case 3 and erected midway inside the mission case 3. The input shaft 11, the PTO transmission shaft 12, the drive shaft 13, the power shift shaft 14, and the counter shaft 1 are concentrically arranged.
5 and a reduction shaft 16 are provided along the front-rear direction from the upper side to the lower side in this order. As shown in FIG. 2, a small-diameter output bevel gear 17 is integrally formed at the rear end of the reduction shaft 16, and a rear wheel differential device is installed at a lower position in the rear half of the transmission case 3. The output bevel gear 17 is meshed with the large diameter input bevel gear 18,
A reduction shaft 16 is interlocked and connected to the four rear wheels. Further, the reduction shaft 16 is supported by a support cylinder 19 fixed to the front end of the case body 3A.
A front wheel drive force output shaft 20 is provided concentrically with the front wheel drive force output shaft 20, a front wheel drive clutch 21 is provided between the reduction shaft 16 and the front wheel drive force output shaft 20, and the front wheel drive force output shaft 20 is connected to the transmission shaft 6 (FIG. 1). A reduction shaft 16 is interlockingly connected to the front wheels 5 so as to be able to connect and disconnect. Further PTO
A transmission shaft 23 is arranged concentrically with the transmission shaft 12 and connected to the transmission shaft 12 by a coupling 22, and is provided above the rear half of the transmission case 3, and the rear end of this transmission shaft 23 is connected to the PTO shaft 10. Reduction gears 24 and 25 are transmitted from the transmission shaft 23 to the PTO shaft 10 facing upward.

Similarly, as shown in FIG. from the drive shaft 13 to the reduction gear 2
6,27 transmission. Also, a small diameter gear 28 fitted to the front end of the power shift shaft 14
By meshing with a large-diameter gear 29 fitted to the front end of the counter shaft 15, transmission is transmitted from the power shift shaft 14 to the counter shaft 15 through the reduction gears 28, 29.

In the transmission mechanism outlined above, the power shift shaft 14 and the counter shaft 15
A hydraulic clutch type transmission 30 as described below, which constitutes the main transmission of the traveling system, is disposed between them. That is, as shown in FIG. 2, on the drive shaft 13, in addition to the gear 27, there are three gears 31, 32,
33 is fixedly installed, and the power shift shaft 1
Four gears 34, 35, 36, 37 are loosely fitted on the drive shaft 13, and among them, the gears 27, 31, 32 on the drive shaft 13 and the gears 34, 35, 36 on the power shift shaft 14 The gears 33 on the drive shaft 13 and the gear 37 on the power shift shaft 14 are rotatably supported on the support wall 3b as shown in FIG. are indirectly engaged through an idler gear 38. Each gear 34, 3 is loosely fitted on the power shift shaft 14.
5, 36, 37 and on the power shift shaft 14 are multi-plate hydraulic clutches 39, 40, 41,
42 are installed. Each hydraulic clutch 39,4
0, 41, 42 are clutch housings 39a, 40a, 4 fixedly installed on the power shift shaft 14.
1a, 42a and each gear 34, 35, 36, 37, friction elements for a plurality of sheets are slidably supported, and the clutch housings 39a, 40a, 4
Pistons 39b, 40b, 41 in 1a, 42a
The pistons 39b, 40b, 41b, 4 resist the return spring force by supplying hydraulic pressure behind b, 42b.
2b is moved forward to engage the friction elements and obtain clutch operation.

As described above, the hydraulic clutch type transmission 30 selectively operates each hydraulic clutch 39, 40, 41, 42 by hydraulic action, and each corresponding gear 34,
35, 36, 37 selectively power shift shaft 14
, depending on the operation of the hydraulic clutch 40, the transmission ratio F ₁ of the first forward speed is achieved, and depending on the operation of the hydraulic clutch 41, the transmission ratio F ₂ of the second forward speed is established, and the hydraulic clutch 39 Depending on the operation of the hydraulic clutch 42, the transmission ratio _F3 is the third forward speed, and the transmission ratio R is the first reverse speed, depending on the operation of the hydraulic clutch 42.
selectively drive shaft 13 and power shift shaft 1
It is configured to interlock and connect the four.

As shown in FIG. 2, the support wall 3a supports the front end of the power shift shaft 14 via a bearing 43, and as shown in FIGS. There is an oil road plate 4 on the upper half of the front.
4 is mounted with a fixture 45. As shown in FIGS. 2 and 4, a hydraulic pump 46 having a pump shaft 46a disposed concentrically with and in front of the input shaft 11 is mounted on the upper front surface of the oil passage plate 44. The pump shaft 46a is connected to the input shaft 11 by a coupling 47, so that input to the transmission mechanism is performed through the pump shaft 46a, and the hydraulic pump 46 is connected to the hydraulic clutches 39, 40, 41, 42. It is supposed to supply hydraulic oil. hydraulic clutch 39
The control valve that controls the supply and discharge of hydraulic oil to and from the control valve 42 is composed of a spool 48 shown in FIG. 49P and 4 clutch ports 49F ₁ ,
49F ₂ , 49F ₃ , 49 respectively refer to the oil passage plate 4.
4 is opened to the inner surface position.

On the other hand, as shown in FIGS. 3 and 5, hydraulic clutches 40, 41, 39, 4 are disposed within the power shift shaft 14.
2, the pistons 40b, 41b, 39b, 42
Hydraulic oil oil passages 50F ₁ , 50F ₂ , 50F ₃ , 50R that are connected to each other behind b, and lubricating oil oil passage 50L that is connected to the friction element portion of the hydraulic clutch 39-42. and are formed respectively. and oil passages 50F ₁ , 5 for hydraulic oil.
As usual, 0F ₂ , 50F ₃ , and 50R are annular grooves formed on the peripheral surface of the front end of the power shift shaft 14, and the open ends thereof are sealed to form oil distribution chambers shown in FIGS. 2 and 6. 51F ₁ , 51F ₂ , 51F ₃ , 51R
The base end or the front end communicates with an annular groove formed with a lubricating oil passage 50.
L is an oil chamber 5 formed in front of the power shift shaft 14
It is connected to 1L.

The oil passage for supplying and discharging hydraulic oil to the hydraulic clutches 39, 40, 41, and 42 is connected to the clutch port 4 described above.
The oil distribution chamber 51F ₁ is completed by connecting the corresponding ones of the oil distribution chambers _{9F 1} , 49F 2 , 49F ₃ , 49R and the oil distribution chambers 51F 1 , 51F ₂ , 51F ₃ , _51R . In order to seal the open end of the annular groove on the circumferential surface of the front end of the power shift shaft 14 in order to form -51R, the following configuration is adopted.

That is, as shown in FIGS. 2 and 6, the oil distribution chamber 51
An annular groove for forming F ₁ -51R is formed intermittently on the front end peripheral surface of the power shift shaft 14 over a length range spanning the oil passage plate 44 and the support wall 3a, and is used for oil distribution. The chamber 51F ₂ seals the open end of the annular groove with the support wall 3a, and the oil distribution chamber 51F ₁ ,
_51F3 are each formed by sealing the open end of the annular groove with the oil passage plate 44. In particular, the oil distribution chamber 51R is provided at a position where the support wall body 3a and the oil passage plate 44 meet, and
A and the oil passage plate 44 seal the open end of the corresponding annular groove.

Clutch port 49 of said control valve with spool 48 as shown in FIG.
F ₁ , 49F ₂ , 49F ₃ , 49R are connected to corresponding oil distribution chambers 51F ₁ , 51F ₂ , 51F ₃ , 51R by oil passages 52F ₁ , 52F ₂ , 52F ₃ , 52R, respectively. Of these, clutch port 4
Oil passage 52R connecting 9R and oil distribution chamber 51R
A slot 52R _a on the inner surface of the oil passage plate 44, a hole 52R b bored in the oil passage plate 44 to connect the groove 52R _a to the front side of the oil passage plate 44, and a hole 52R _b on the oil passage plate 44. A slot 52R _c formed on the mating surface of the hydraulic pump 46 with the pump case, and a hole 52R _d drilled in the oil passage plate 44 to connect the slot 52R _c to the back side of the oil passage plate 44. , the slot 52 on the inner surface of the oil passage plate 44
R _e and a slot 52R _f formed in the mating surface of the oil passage plate 44 and the support wall 3a. The other oil passages 52F ₁ , 52F ₂ , and 52F ₃ are similarly provided using the oil passage plate 44, the support wall 3a, and the pump case. Note that the oil path leading to the oil inlet of the hydraulic pump 46, the hydraulic pump 46
An oil passage connecting the oil discharge port of the control valve and the pump port 49P, an oil passage connecting the tank port of the control valve and the inside of the transmission case 3 which also serves as an oil tank, and a support wall similar to the control valve, although not shown. The oil passage for the pressure regulating valve mechanism built into the body 3a is also provided using the oil passage plate 44, the support wall 3a, and the pump case of the hydraulic pump 46, similar to the above.

In FIG. 5, reference numeral 54 denotes an operating shaft rotatably supported on both side walls of the case body 3A, which is interlockingly connected to the spool 48 at the lower end side of the spool 48 within the mission case 3. ,
It is interlocked and connected to a main shift lever (not shown) outside the transmission case 3, and is used to displace and operate the spool 48. Also, in Figures 2 and 6, 5
Reference numeral 5 denotes a brake for automatically braking the power shift shaft 14 when the hydraulic clutch type transmission 30 is in a neutral state, and is known from, for example, Japanese Patent Publication No. 51-20170.

As shown in FIG. 2, the above-mentioned counter shaft 15
A gear shift type transmission 56 constituting a traveling system auxiliary transmission is disposed between the reduction shaft 16 and the reduction shaft 16 . This gear shift type transmission 56 has two gears 57 fixedly installed on the counter shaft 15,
Two shift gears 59 and 60 are provided on the reduction shaft 16 so as to be able to slide freely, and the claws 29a on the inner peripheral surface of the shift gear 59 can be selectively engaged with the claws 29a as described above. It is formed integrally with the gear 29 and is configured to be able to selectively obtain three speed change ratios.

Similarly, as shown in FIG.
A PTO transmission 62 is installed above the front half of the transmission case 3 and is capable of selectively interlocking the PTO transmission shaft 12 and the PTO transmission shaft 12 at any one of three speed ratios. This PTO transmission 62 has two gears 63 and 64 meshed with the gears 31 and 32 on the drive shaft 13, which are loosely fitted onto the PTO transmission shaft 12, and a pawl 65 at the end of the input shaft 11. Each gear 63, 64 is provided with a shift metal fitting 66 formed on the PTO transmission shaft 12 so as to be slidable only.
The pawls 63a and 64a formed on the cylindrical shaft 63a and the pawl 65 can be meshed and engaged with each other, and are provided with three gear stages.

Next, FIG. 7 shows another embodiment. In this other embodiment, instead of the oil passage plate 44, an oil passage transfer tube 70, which is blind on one side, is installed in the oil distribution chamber 51 together with the support wall 3a.
It is used as a seal body for forming F ₁ , 51F ₂ , 51F ₃ , and 51R. That is, the oil passage pipe 70 is provided with a fixture 7 on the outer surface or front surface of the support wall 3a.
1 and is fitted onto the front end of the power shift shaft 14, and is involved in the formation of the oil distribution chambers 51F ₁ , 51F ₃ and 51R in exactly the same way as the oil passage plate 44 in the previous embodiment. Hydraulic clutch 4 for reverse 1st gear
Similar to the previous embodiment, the oil distribution chamber 51R communicated with the oil distribution chamber 51R is provided at a position where the supporting wall body 3a and the oil passage transfer tube 70 meet.

Note that, unlike in the above embodiments, the supporting wall body 3a may be a plate body separate from the mission case 3 or the case body 3A.

As is clear from what has been explained above, the oil passage forming device for a hydraulic clutch type transmission of this invention has a plurality of hydraulic clutches 39, 40, 4.
The plurality of hydraulic clutches 39, 1, 42 are mounted on the circumferential surface of one end of the power shift shaft 14 through the plurality of oil passages _50F1 , _50F2 , _50F3 , 50R drilled in the power shift shaft 14. 40, 41, and 42 are formed, and the open ends of the plurality of annular grooves are sealed with a fixed seal body fitted onto one end of the power shift shaft 14,
An oil passage for a hydraulic clutch type transmission in which a plurality of oil distribution chambers 51F ₁ , 51F ₂ , 51F ₃ , 51R for the plurality of hydraulic clutches 39, 40, 41, 42 are formed on one end of the power shift shaft 14. The forming device includes a support wall body 3a that supports the fixed seal body on one end side of the power shift shaft 14 via a bearing 43, and another seal body mounted on the outer surface of the support wall body 3a. 44 or 70, and the above-described plural oil distribution chambers 51F ₁ , 51F ₂ ,
51F ₃ , one oil distribution chamber 51R among 51R
The supporting wall body 3a and other seal bodies 44, 7 described above
0, and the oil distribution chamber 51R side end of the oil passage 52R for supplying and discharging hydraulic oil to the one oil distribution chamber 51R is connected to the above-mentioned support wall 3a and other It is characterized by being constructed with a slot 52Re formed in the mating surface with the seal bodies 44, 70, and has the following advantages.

That is, the oil path forming device of this invention seals the open end of the annular groove on the circumferential surface of the power shift shaft on one end of the power shift shaft to form a plurality of oil distribution chambers. As explained at the beginning, conventionally a single member was used as the fixed seal member to be fitted, such as a cylinder with one side blind or a support wall that also served as the shaft end support member. Breaking away from the conventional wisdom of using a single member, we have developed a support wall 3a that supports the shaft end of the power shift shaft 14, and another seal member 44 mounted on the outer surface of the support wall 3a. 70 constitutes a seal body for forming multiple oil distribution chambers 51F ₁ -51R, and the number of oil distribution chambers increases as the number of hydraulic clutches loaded on the power shift shaft increases. Even when the number of oil distribution chambers is increased, the range in which the plurality of oil distribution chambers are formed is covered by two members. Unlike conventional models, the power shift shaft does not have to be elongated, and multiple oil distribution chambers are formed within the width of the support wall that supports the shaft end. Unlike conventional models, the thickness of the support wall must be increased. Therefore, the length of the power shift shaft 14 can be shortened and the thickness of the support wall 3a can be reduced.

Also, multiple oil distribution chambers 51F ₁ , 51F ₂ , 51F ₃ ,
The oil passage on the fixed position side leading to 51R is formed at the mating surface position of the support wall 3a and the other seal body 44 or 70, that is, on the outer surface of the support wall 3a and the other seal body 44. Alternatively, the simplest method is to integrally form a slot on one or both of the inner surfaces of 70 during casting, and then seal the peripheral edge of such a slot with a mating surface. In contrast, the oil path forming device of this invention has multiple oil distribution chambers 51F ₁
-51R is disposed across the support wall 3a and the other seal body 44 or 70,
Each oil distribution chamber 51F ₁ , 51F ₂ , 5 from the above mating surface
1F ₃ , 51R is shortened, and from this, the oil passage at the mating surface position is connected to each oil distribution chamber 51.
The oil passages for connecting to F ₁ , 51F ₂ , 51F ₃ , and 51R are shortened, and such oil passages can be easily formed.

In particular, the open ends of the plurality of annular grooves on the circumferential surface of one end of the power shift shaft 14 are sealed by two members, the support wall 3a and the other sealing body 44 or 70, thereby forming the plurality of oil distribution chambers _51F1- 51R, one oil distribution chamber 51R is arranged at a position where the supporting wall 3a and the other sealing bodies 44, 70 meet, and the supporting wall 3a and the other sealing bodies 44, 70 are connected. Since it is assumed that both members are sealed, the total thickness of the supporting wall body 3a and the other seal bodies 44 and 70 when viewed in the axial direction of the power shift shaft 14 is equal to the total thickness of the plurality of oil distribution chambers 51.
F ₁ -51R is effectively utilized to shorten the length of the power shift shaft 14 and support wall 3.
The above-mentioned advantages such as reduced thickness of a are further enhanced,
In addition, an oil passage 52R for supplying and discharging hydraulic oil to the above-mentioned one oil distribution chamber 51R is connected to the oil distribution chamber 51R by a groove 52Re formed in the mating surface of the support wall 3a and the other seal bodies 44, 70. Since the communication is made, such a slot 52Re is connected to the support wall 3a.
Since the other seal bodies 44 and 70 can be formed simultaneously during casting, the above-mentioned advantage that oil passages can be easily formed is further enhanced.

[Brief explanation of the drawing]

Fig. 1 is a side view of an agricultural tractor equipped with an embodiment of this invention, Fig. 2 is a partially exploded longitudinal sectional side view of the main parts of the same tractor, and Figs. 3 and 4 are, respectively.
Fig. 5 is an enlarged longitudinal sectional view taken approximately along the - line and - line in Fig. 2, Fig. 6 is an enlarged view of the main part of Fig. 2, 7
The figure is a longitudinal sectional side view showing the main parts of another embodiment. 3...Mission case, 3A...Case body,
3a... Support wall body, 13... Drive shaft, 14... Power shift shaft, 27... Gear, 30... Hydraulic clutch type transmission, 31, 32, 33... Gear, 3
4, 35, 36, 37... Gear, 38... Idler gear, 39, 40, 41, 42... Hydraulic clutch, 39a, 40a, 41a, 42a... Clutch housing, 39b, 40b, 41b, 42b
... Piston, 43 ... Bearing, 44 ... Oil path plate, 45 ... Fixture, 46 ... Hydraulic pump, 4
8...Spool, 49F ₁ , 49F ₂ , 49F ₃ , 4
9R...Clutch port, 50F ₁ , 50F ₂ , 5
0F ₃ , 50R... Oil path, 51F ₁ , 51F ₂ , 51
F ₃ , 51R...Oil distribution chamber, 52F ₁ , 52F ₂ , 5
2F ₃ , 52R...oil passage, 70...oil passage pipe,
71...Fixing tool.

Claims (1)

[Scope of utility model registration request] A plurality of annular grooves are formed on the circumferential surface of one end of the power shift shaft on which the plurality of hydraulic clutches are mounted, and the plurality of annular grooves are communicated with the plurality of hydraulic clutches through a plurality of oil passages drilled in the power shift shaft. The open end of the annular groove is sealed with a fixed sealing body fitted onto one end of the power shift shaft to form a plurality of oil distribution chambers for the plurality of hydraulic clutches on the one end of the power shift shaft. An oil passage forming device for a hydraulic clutch type transmission includes a supporting wall body 3a that supports the fixed seal body on one end side of the power shift shaft 14 via a bearing 43, and this supporting wall body. Another seal body 4 mounted on the outer surface of 3a
4, 70, and one of the plurality of oil distribution chambers 51F ₁ , 51F ₂ , 51F ₃ , 51R described above.
A number of oil distribution chambers 51R are provided at positions where the supporting wall body 3a and the other seal bodies 44 and 70 meet, and oil for supplying and discharging hydraulic oil to the one oil distribution chamber 51R is provided. The oil passage forming device is characterized in that the end of the passage 52R on the side of the oil distribution chamber 51R is constituted by a slot 52Re formed in the mating surface of the support wall body 3a and the other seal bodies 44, 70.